Mutex Stored Procedure

Question

I want to create some distributed mutual exclusion using a database table. It would be nice to have the following interface on a stored procedure:

Wait(uniqueidentif

Answer 1

Take a look at the system stored procedure:

 sp_getapplock

It may help you accomplish what you are trying to do.

http://msdn.microsoft.com/en-us/library/ms189823.aspx

You can put it in a proc that parametrizes the uniqueidentifier...

BEGIN TRAN

DECLARE @result int

EXEC @result = sp_getapplock @Resource = 'YOUR_uniqueidentifier_HERE', 
                             @LockMode = 'Exclusive',
                             @LockTimeout = 90

IF @result NOT IN ( 0, 1 )   -- Only successful return codes
BEGIN
  PRINT @result
  RAISERROR ( 'Lock failed to acquire...', 16, 1 )
END 
ELSE
BEGIN
    -- DO STUFF HERE 
END
EXEC @result = sp_releaseapplock @Resource = 'YOUR_uniqueidentifier_HERE'  

COMMIT TRAN